Angelina Jolie has been praised by officials at the United Nations following her appointment as a special envoy for the organisation, with bosses insisting the actress goes "substantially beyond" expectations in her work.

The Mr. & Mrs. Smith star served as a UN goodwill ambassador for more than 10 years and officials promoted her to the new role in their refugee agency to represent the UN to governments and diplomats around the world.

And her continued humanitarian efforts, in countries including Iraq, Haiti and Pakistan, have been praised by the organisation.

Spokesman Adrian Edwards says, "Her work does go substantially beyond what we would typically see as being the normal role of a goodwill ambassador. I don't think you need a rocket scientist to see the benefits that she is bringing in terms of the attention that she is getting for the plight of the world's displaced."